This invention concerns a telescopic grenade, for instance, a grenade designed to be launched by means of a rifle and fitted with a caliber ring. We are already familiar with telescopic projectiles provided with a head extended by a tubular tail and containing an explosive charge as well as a detonator chain for the latter, with the aforesaid tail made of two telescopic tubular parts, one of which is firmly attached to the aforesaid head and carries together with the latter a first section of the aforesaid detonator chain, with the other part carrying the remaining section of this chain and with guiding means distributed on the aforesaid two parts so as to provide them with a specific angular position, depending on their relative axial position.